Generating new chunks is painfully slow

Since updating to 1.16 we have got chronic lag when players generate new chunks. Only minor changes to the command system (to account for checking the dimension a player is in)

No change to the server host. We have 6G Ram - we were fine with up to about 10 players on 1.15. Now it can barely manage 4 or 5. It has been very close to unplayable.